Maria conducted an experiment to determine whether showing college students a video about the origins of racial prejudice decreases their level of prejudice. She gave the experimental group a pretest to measure their level of prejudice, showed them the film, and then gave them a posttest to again measure their level of prejudice. The control group saw a wildlife film and took the pretest and posttest. The results of the study showed that watching the video about the origins of racial prejudice decreased the prejudice of the experimental group compared to the control group. What might be a source of external invalidity for Maria's study?
A)The pretest might have sensitized the students to their prejudice, so they changed their answers for the posttest.
B)An event might have occurred during the course of the experiment that affected the experimental group's views of racial prejudice.
C)Statistical regression may have affected the experimental group.
D)There may have been selection biases that affected the control group.
E)The pretest might have sensitized the experimental group members to their bias, so they were more impacted by the film.

Question

Quizplus · Accepted Answer

The pretest might have sensitized the experimental group members to their bias, making them more receptive to the film's message, which could limit the generalizability of the results to a broader population that did not take a pretest.

Maria Conducted an Experiment to Determine Whether Showing College Students